Hi Dan, On Fri, Aug 30, 2019 at 11:34:45AM +0300, Dan Carpenter wrote: > On Fri, Aug 30, 2019 at 12:04:41AM +0800, Gao Xiang wrote: > > Anyway, I'm fine to delete them all if you like, but I think majority of > > these > > are meaningful. > > > > data.c- /* page is already locked */ > > data.c- DBG_BUGON(PageUptodate(page)); > > data.c- > > data.c: if (unlikely(err)) > > data.c- SetPageError(page); > > data.c- else > > data.c- SetPageUptodate(page); > > If we cared about speed here then we would delete the DBG_BUGON() check > because that's going to be expensive. The likely/unlikely annotations > should be used in places a reasonable person thinks it will make a > difference to benchmarks.
DBG_BUGON will be a no-op ((void)x) in non-debugging mode, I discussed related stuffs with Greg many months before [1] and other filesystems also have similar functions... p.s. I think we come to an agreement here... I killed all unlikely/likely. [1] http://driverdev.linuxdriverproject.org/pipermail/driverdev-devel/2018-November/128951.html sorry about no lore here. Thanks, Gao Xiang > > regards, > dan carpenter >
